Process of making rubberized fiber composition



Patented Feb. 10, 1925.

UNITED sra'r is 1,526,298 PATENT OFFICE.

BbBLEY H. KC JBBISON, OE AKRON, OHIO, Z WQIGiNOR TO THE GOODYEAR TIRE &

RUBBER comm, OF 'AKRil:

OI-L A CORPORATION OF OHIO.

PBOGZNS O l MAKING FIBEB'GOMPOSITION.

Ho Drawing.

To all whom it mag concern:

Be it known that I, RoBLn'Y H. Monuison,

a citizen of the United States, residin at Akron, in the county of Summit and tate I of Ohio, have invented new and useful Imrovements in Processes of Makin I erized Fiber Composition, of which the following is a specification. My present invention relates to a process "for the manufacture of a material capable of many useful applications, such as for floor and wall coverings, as a substitute for leather, forcontainers of liquids or of moist materials and for other purposes to which a tough, flexible, waterproof body may be adapted. More specifically, -my invention consists in treatin fibers in such manner as to saturate an thoroughly impregnate them with a binding material, thereby ren- 9 during it possible to compact and mold the product to any degree and in any way desired. As such a binding material I may use rubber, gutta-percha or other substances of a like nature which may bevulcanized when heated with sulfur or-other curing agents.

The fibers, which are capable of being treated according to the details of my process as hereinafter; disclosed, should preferably be shortbut are not limited to any one kind or type. Thus, forexample, I ma use-cotton, 1inn,-hemp, manila, jute, ashe tos,ior wood fibers as prepared -for paper making, or any felting material, such as I hair or fur. or other materials of' a like nature. With fiber or mixture of fibers, I combine a substance, such as rubber, oil or gumwhich may be-readilydi'ssolved and precipitated from its solution upon the fibers and which, furthermore, is susceptibleto yulcanization with sulphur by heat or by any other suitable method. In this way, I'obtaina product, all the fibers of which are apparently coated with the impregnating material and which is tough, flexible, waterproof and capable of being compressed and molded into any desired form and then vulcanized.

My preferred process for the manufacture P of this composition is as follows: The fibers,

referablywood pulp fibers and particu- Fa'rly that-brand known as sulphate kraft or that produced from wood by the well known'sulphite orsodaproccss, are beaten with a liquid in anordinary beating engine- Rub-- Application filed mum is, 1921. Serial No. 522,047.

machine used for a like purpose in the paper industry. The consequent disintegration should leave the material in a fibrous condition and particular care should be taken not to comminute or break down the fibers any more than is unavoidable in the process. As the li uid to be used in the beater with the pulp, may use one that will serve as a solvent for or as a. precipitating agent of the gum-used. When rubber is used as the gum and is precipitated from a benzol or a gasoline solution, I prefer-to use wood or denatured alcohol as the beating agent for the fibers. In the place of alcohol, I may use any liquid which is miscible with that addedas a solvent or carrier of the or rubber. In order to obtain the best result, the pulp should be dried before being placed in the beater. This is advisable in order to prevent unnecessary dilution of the alcohol, or other liquid, which should always be avoided if a solvent miscible with water is used. .The drying of the fibers would of course, be unnecessary in case water be used .amountxof fibers used is from 2% to about of well known form or in any other similar 8% of the weight of liquid taken; 'In any case, it must not be so large. an amount that a thick mass of wettedfibers is produced but must form a fluid mixture in which the individual fibers may be separated from one another as completely as possible. The

mixture is then beaten up until the mass of fiber is thoroughly disintegrated. It has been found that a more". uniform coating is-formed upon the individual fibers if the liquid, preferably a non-solvent of rubber, which 1s initially utilized as a suspension means in which the fibers are beaten, is drained oil to a great extent and the result-- ing product then mixedfwith a rubber solvent. There is now added to the mixture in a tank a sufiici'entquantity of rubber cement orother substance ofithe required properties to produce a'material containing any desired proportion of rubber to the treated fiber, whichproportion I have found should be varied according to the ultimate requirements of the finished product. Thus,

for a substitute for leather in the making of soles and heels l: have found that a mixture of about 33% dry rubber and 67% dig pulp gives the best results, although ot er proportions will yield a material of high quality.

The disintegrated fibers are a itated in the rubber solution for a period of time sufiicient to thoroughly intermix and incorporate the materials together. The time required to accomplish this WilLot course, vary according to the composition of the cement taken and the amount used. The solvents used for the. cement and as a medium in beating up the pulp or other fibers should preferably be miscible with one another but one of them should be a nonsolvent for rubber. By the use of such a combination of liquids, the rubber is precipitated on the fibers of the pulp or of any other fibrous material which it is desired to treat in this manner.

The rubberized fibers are then removed from the liquid mixture, by an desirable method, such as screening, and the liquids are allowed to drain away. The drying or removal of the liquids may be aided by means of pressure, which may be applied to the fibers in a mold. It is possible to shape the mass of rubberized fibers in any desired form and then to heat cure them under any desired or necessary pressure and temperature to vulcanize the rubber present and to form a compact mass which may be used for any desired purpose as hereinbefore mentioned.

The rubber cement which I prefer to use may be composed of any proportion of rubbar and solvent that is desirable as Well as practicable. The concentration of cement and the amount added Will be decided by the qualities desired in the finished material. There is preferably some curing agent, such as sulfur, present in the cement, and there may or may not be added accelerators, filling agents, or compounding ingredients. Moreover, the time required to cure the finished material will vary according to the composition of the cement used.

It is to be understood that the proportion of rubber or gum that is mixed with the fibers in the making of my composition is an amount sufficient to bind together the fibers used and may or may not predominate liquid in a comparatively loose state.

in the mixture. it is an essential point in my invention that the rubber or gum ishomogeneously distributed about the fibers as completely as possible and, this result I accomplish by adding a solution or' cement or rubber to the fibers suspended in soine nstead of following theprocesfils outlined, it is also possible to obtain e ually beneficial and, with some fibers, more esirable results, by beating the fibers in a solvent of rubber,

While I have described in more or less 7 detail the specific steps of my process and have given particular solvents, chemicals or other reagents used in practicin the method, it Will be understood that the c aims hereto appended define the invention and I do not mean to be limited in any Way except by them. Furthermore, my invention is not to be regarded as dependent on the sound nose or accuracy of any theories herein propounded.

What I claimis:

1. A method of treating fibers that oom v E prises agitating the fibers in a. non-solvent of rubber, removing a portion of the non-solvent, mixing the'fibers in a solvent of rubher. adding a solution of rubber thereto, precipitating the rubber on the fibers, removing the treated fibers and vulcaniaing.

2. A. method of treating fibers that comprises agitating the fibers in a non solvent of rubber, removing a portion or the non-solvent, mixing the fibers in a solvent of rubber. adding a solution of rubber thereto, pro-- cipitating the rubber on the fibers, removing the treated fibers, drying and vulcanizing the product. a

3. A method of treating fibers that comprises agitating the fibers in a non-solvent 3.

of rubber, removing a portion of the nonsolvent,-rn1xmg the fibers in a solvent of rubber, adding a solution of rubber thereto,

till

adding a precipitating agent to the mix,

removing the treated fibers and vulcanizing the product.

4-; A method of treating fibers that con prises agitating the fibem in a non-solvent of rubber, removing a portion of the nonsolvent, mixing the fibers in a solvent of rubber, adding a solution of rubber thereto, adding a precipitatin agent to the mix, removing the treated fibers, drying and vulcanizing the product.

5. A method of treating fibers that comprises beating the fibers in alcohol, removing a portion of the alcohol, associating the fibers with a solvent of rubber. adding a. solution or rubbcr thereto, precipitating the rubber on the fibers. removing the treated fibers and vulcanizin'g the product.

6. A method of treating fibers that comprises beatin the fibers in alcohol, removing a portion 0% the alcohol, associating the fibers with a solvent oi rubber, adding a solution of rubber thereto, precipit-ating tire ubber on the fibers, removing the treated fibers, drying and vulcanizing the product.

7.1 3. method of treating fibers that comprises beating the fibers in alcohol, removmg a portion of the alcohol, associating the fibers with a solvent of rubber, mixing a solution, of rubber therewith, adding a nonsolvent .of rubber .to precipitate the rubber on the fibers, removing the treated fibers and Ivulcanizing. v

8. A method of treating fibers. that comprises beating the fibers in a non-solvent of rubber, removing a portion-of the non soll. vent, associating a rubber solvent with the bers, reparing a rubber solution of rubher an a solvent the same as that previously utilized, adding the rubber solution thus prepared to the liquid'containing the fibers,

ll precipitating the rubber onthe fibers, re-

moving the treated fibers, drying and vulcanizing the product. I

tion of benzol and rubber, adding the rubber solution to the fiber mix, precipitatin the rubber on the fibers by adding alcoho removing the treated fibers, drying and vulcanizing the product.

In witness whereof I have hereunto si ned my name in the presence of two'subscri ing witnesses. ROBLEY H. MORRISON. Witnesses J. P. MAID O. E. Bra 

